Expandable core-former



Oct. 18, 1966 l.. D. LONG 3,279,740

EXPANDABLE CORE-FORMER Original Filed Aug. 25, 1960 2 Sheets-Sheet lFIG. @94 70@ '70a 7 @9e 7/9 70e BY' 694 Mg M Mu? 770 FIG. 5 'LHTroRNEs/s.

'ct 18, 1966 L. D. LONG 3,279,740

l' EXPANDABLE CORE-FORMER original Filed Aug. 25, 1960 I 2 sheets-sheet2 FIG.` s

688 686 INVENTOR.

United States Patent 3,279,740 EXPANDABLE CORE-FORMER Leonard D. Long,Long Construction Co., P.0. Box 288, 2110 Mount Pleasant St.,Charleston, S.C.

Application Aug. 1, 1962, Ser. No. 215,218, now Patent No. 3,210,039,dated Oct. 5, 1965, which is a division of application Ser. No. 51,972,Aug. 25, 1960, now

Patent No. 3,090,093, dated May 21, 1963. Divided and this applicationJuly 19, 1965, Ser. No. 472,786

4 Claims. (Cl. 249-181) This invention relates to a core-former, andmore particularly to an expandable core-former for producing cores incored building blocks and the like. This application is a division of mycopending application Serial No. 215,218, tiled August 1, 1962, nowPatent No. 3,210,039, yissued October 5, 1965, which is a division of myapplication Serial No. 51,972, filed August 25, 1960, now Patent No.3,090,093, issued May 21, 1963.

It is an object of my invention to provide a coreformer which can beexpanded by a rotational thrust force, which can be uniformly expandedthroughout its length, which can be expanded against the action ofsubstantial counter-forces, which can be maintained in a xed positionand orientation during its expansion, and which wi-ll prove sturdy anddurable in use.

In accordance with one form of my invention, the core-former comprises aplurality of core segments having inwardly presented thrust-receivingfaces which are operatively engaged by thrust-transmitting cam meansmounted on a first shaft interposed between the core segments androtatable to `cause said cam means to move the core segments into spacedrelation to each other for expanding the core-former. Conveniently, thecore segments are operatively interconnected whereby upon reverserotation of said first shaft said core segments will be moved towardeach other to collapse the core-former. A second shaft is disposedaround the first shaft and is operatively interconnected to the coresegments for moving the core-former to and from an operative position ina mold.

A plurality of face plates are operatively connected to the severa-lcore segments to bridge the spaces between said segments and prevent theentry of the material being cored from entering into the interior .ofthe core-former from the sides thereof when said core-former isexpanded. Plate means are interposed between the opposed ends of thecore segments and cover plates on the ends of the face plates to preventthe material being cored from entering into the interior of thecore-former from the ends thereof.

Other objects and features of my invention will become apparent from themore detailed description which follows and from the accompanyingdrawings, in which:

FIG. 1 .is a vertical section through an expandable core-formerembodying my invention;

FIG. 2 is a horizontal section taken on the line 2-2 of FIG. 1;

FIG. 3 is a horizontal section taken on .the line 3 3 of FIG. 6;

FIG. 4 is a fragmentary enlarged vertical section of the core-formershown in FIG. 1, but taken on an oblique core-former axis and showingthe core-former in expanded position;

FIG. 5 is a horizontal section taken on `the line 5 5 of FIG. 1, butshowing portions of the core-former broken away;

FIG. 6 is a vertical section similar to FIG. 1, but showing thecore-former in expanded position;

3,279,740 Patented Oct. 18, 1966 ICC FIG. 7 is an enlarged isometricview of the spider block shown in FIG. l;

FIG. 8 is an enlarged isometric View of the pilot block shown in FIG. l;

FIG. 9 is a fragmentary enlarged vertical section similar to FIG. 4, butshowing the opposite end Iof the coreformer; and

FIG. 10 is a bottom plan view of the core-former shown in FIG. l, butwith portions thereof broken away.

My core-former is adapted to be used in combination with an apparatus ofthe type disclosed in my U.S. Patent No. 3,090,093, issued May 2l, 1963,for producing molded components having cores formed therein. Theconstruction of my core-former is such that it can be inserted in acollapsed condition into an appropriate mold prior to the addition ofthe material to be molded, and then expanded to compress said materialagainst .the inwardly presented mold walls. This permits the formationof high-density molded articles having cores formed therein.

For ease of description, the core-former is described herein as beingused to produce cored building blocks formed from an aggregate mixture.It is to be understood, however, that my core-former can be used forproducing various other types of cored elements.

The core-former is movable into and out of operative position in a moldby means of a shaft 675 projecting outwardly from its connect-ion -tothe core-former. As shown in FIG. 1, the lower end of the shaft 675 isthreadably connected to a spider block 678 having a plurality ofoutwardly projecting arms 680 disposed on the oblique core-former axes.The core-former is expanded by means of a rotatable shaft 682 extendingupwardly through the shaft 675 for connection to a rotational powersource. A quadri-loaded cam 684 whose cam lobes are disposed on thetransverse core-former axes when said core-former i-s in its collapsedposition is mounted on the lower end of the shaft 682. As shown in FIG.1, the upper face of the cam 684 is rotatably slidable against the lowerface of the spider block 678, and the lower face of said cam isrotatably slidable on the upper face of a second spider block 686rotatably connected to the lower end of the shaft 682, as by a bolt 688.The spider block 686 also has a plurality of outwardly projecting arms690 parallel to the spider arms 680, and is further provided with apilot 692 projecting outwardly from the lower end of the core-former forreception in an opening in the bottom of a mold to engage the facesthereof and prevent the core-former from rotating in the mold.

As shown in FIG. 2, the core-former is provided with four elongated coresegments 694, eac-h of which has a pair -of outer faces normal to eachother and an inner face provided with an inwardly projecting camfollower 696 which is receivable between a pair of lobes on the cam 684when the core-former is in its collapsed position. Adjacent each of itsends, each of the cam followers 696 is provided with openings 698adapted to slidably receive the spider arms 680 and 690 whereby saidarms will guide the movements of the core segments during expansion andcollapse of the core-former. A second set of openings 699 is also formedin each of the cam followers 696 adjacent each of its ends for thereception of coil springs 700 secured to the core segments as by pins702. The

inwardly presented ends of the springs 700 are received in openings 703and 703 formed in spider blocks 678 and 686, respectively, and areretained therein by pins 704. As will be clear from FIGS. 3 and 4, thesprings 700 and the spider arms 680 and 690 are all disposed on the)oblique axes of the core-former.

In order to prevent aggregate from entering the coreformer when it is inexpanded position, I mount a plurality of face plates '706 on theseveral core segments 694. As shown in FlG. 2, each of the face plates766 has a width corresponding to the width of the coreformer incollapsed position so that it bridges the space between a pair ofadjacent core segments when the coreformer is in expanded position. Eachof the face plates 766 has a rib 768 extending inwardly `therefrombetween a pair of adjacent core segments 694 for connection to a slide710 slidably carried in aligned slots formed in the adjacent faces of apair of adjacent core segments. Extending inwardly from the upper andlower ends of the face plates 766 are top and bottom cover plates'712and 7M, respectively. The top cover plates 712 extend inwardly over ascreed plate 716 interposed between said cover plates and the upwardlypresented faces of the spider block 57S and the core segments 694.Similarly, the bottom cover plates 714 extend inwardly over a pilotplate 7i8 interposed between said cover plates and the downwardlypresented faces of the spider blo-ck 686 and the core segments 694.Conveniently, the screed and pilot plates 716 and 718 have lateralextents only slightly smaller than the lateral extent of the core-formerin its collapsed position so that they will act in combination with thecover plates 712 and 714 t-o prevent aggregate from entering the ends ofthe core-former when it is in expanded position. As shown, the edges ofthe face plates 706 and their cover plates 712 and 714 are beveled, asat 719, so that upon collapse of the coreformer said face and coverplates will screed any aggregate from the outwardly presented faces ofthe core segments and the screed and pilot plates.

Thus, `the operation of the core-former shown in FIGS. 1-10 may bedescribed as follows: The shaft 675 is moved axially to position thecore-former in a mold with the pilot 692 seated in an opening formedtherein, and the shaft 682 is rotated through a 45 angle in a clockwisedirection as viewed in FIG. 2 to cause the lobes on the cam 684 to bearagainst the cam followers 697 to thus move the core segments outwardlyin spaced relation to each other on the oblique core-former axes. As thecore segments are moved to their expanded positions, they are guided bythe spider arms 680 and 690 sliding in their respective openings formedin the cam followers 696, and by the face plate slides 710. With thecore segments in this expanded position shown in FIG. 3, the face plates706 bridge the spaces between the spaced pairs of adjacent core segmentsalong the side faces of the core-former to prevent the entry ofaggregate therein. And the top and bottom cover plates 712 and 714cooperating with the spider plate 716 and pilot plate 71S prevent theentry of aggregate from the core-former from the top and bottom thereof.

To retract the core-former to its collapsed position, the shaft 682 isrotated in a countercl-ockwise direction as viewed in FIG. 3. Suchrotation moves the lobes on the cam 684 out of bearing engagement withthe cam followers 697, and the core segments 694 are thus pulledinwardly on the oblique core-former axes by the springs 70). The inwardcollapsing movement of the core segments 694 is also guided by thespider arms 680 and 690 and by the slides 710 on the face plates 706.During this inward movement of the core segments, the beveled edges ofthe face plates 7 06 and the top and bottom cover plates 712 and 714will slide along, and screed any aggregate from, the outer faces of thecore segments 794 and the screed and pilot plates 716 and 718.

I claim:

1. An expandable core-former, comprising a plurality of core segmentsmovable with respect to each other and having cam followers projectinginwardly on the oblique core-former axes, a first shaft movable form-oving the core-former to and from an operative position in a mold,

a first spider block mounted on said first shaft and having a pluralityof outwardly projecting arms slidably received in openings formed in thecore segments adjacent one of their ends, a second shaft rotatablycarried in said first shaft and first spider block and interposedbetween said core segments, cam means on said second shaft rotatabletherewith in one direction to engage said cam followers and force saidcore segments uniformly outwardly from each other to expand thecore-former, a second spider block rotatably mounted on said secondshaft at the end of said cam means remote from said first spider blockand having a plurality of outwardly projecting arms parallel with thearms on said first spider block and slidably received in openings formedin the core segments adjacent their ends remote from Said first spiderblock, spring means interconnecting each of said core segments to saidspider blocks to move Ysaid core segments inwardly upon rotation of thecam means in an opposite direction, said spider block arms and springmeans lying in the planes of the oblique core-former axes, and means onsaid spider blocks and core segments bridging and closing the spacesbetween tops, bottoms, and sides of said core segments.

2. An expandable core-former as set forth in claim 1 in which said cammeans are rotatable against the lower and upper faces of said first andsecond spider blocks, respectively, each of said cam followers extendsbeyond the ends of said cam means and the openings in said core segmentsare formed in said cam followers, to slidably receive the arms of saidfirst and second spider blocks, and said spider blocks and cam followershave aligned openings for reception of said spring means.

3. An expandable core-former, comprising a plurality of core segmentsmovable with respect to each other and having cam followers projectinginwardly on the oblique core-former axes, a first shaft movable formoving the core-former to and from an operative position in a mold, afirst spider block mounted on said first shaft and having a plurality ofoutwardly projecting arms slidably received in openings formed in thecam followers adjacent one of their ends, a second shaft rotatablycarried in said first shaft and first spider block and interposedbetween said core segments, cam means on said second shaft rotatabletherewith in one direction to engage said cam followers to for-ce saidcore segments uniformly outwardly from each other to expand thecore-former, a second spider block rotatably mounted on said secondshaft and having a plurality of outwardly projecting arms parallel withthe arms on said first spider block and slidably received in openingsformed in the cam followers adjacent their ends remote from said firstspider block, means interconnecting said core segments to said spiderblocks to move said core segments inwardly upon rotation of the cammeans in an opposite direction, said spider block arms and said meansinterconnecting the core segments to the spider blocks lying in theplanes of the oblique core-former axes, a pair of screed plates disposedover the opposed ends of said first and second spider blocks andslidably received on the opposed ends of said core segments, a pluralityof face plates mounted on said core segments having cover platesreceived over said pair of screed plates whereby said pair of screedplates and said face and cover plates close and bridge the spacesbetween the tops, bottoms, and sides of said core segments, and ribs onsaid face plates interposed between adjacent pairs of core segments andprovided with slides slidably received in aligned slots formed in saidadjacent pairs of core segments.

4. An expandable core-former as set forth in claim 3 in which saidsecond spider block has a pilot projecting `through one of said pair ofscreed plates for releasably retaining the core-former in anon-rotatable position in a mold.

(References on following page) 5 6 References Cited by the Examiner2,315,634 4/ 1943 McCall 249-179 2 878 545 3/1959 Lowe 25-128 UNITEDSTATES PATENTS 6/1889 Bennett 24g-181 3,064,439 11/1962 Cobl 25-128 X10/1904 shell 249-147 5 FOREIGN PATENTS 6/ 1905 Pettyjohn 249-147 X8,333 2/ 1908 France. 3/ 1906 Landmann. 6/1912 Whitman. J. SPENCEROVERHOLSER, Primary Examiner. 10/ 1942 George 25-41 J. H. FLINT,Examiner.

1. AN EXPANDABLE CORE-FORMER, COMPRISING A PLURALITY OF CORE SEGMENTSMOVABLE WITH RESPECT TO EACH OTHER AND HAVING CAM FOLLOWERS PROJECTINGINWARDLY ON THE OBLIQUE CORE-FORMER AXES, A FIRST SHAFT MOVABLE FORMOVING THE CORE-FORMER TO AND FROM AN OPERATIVE POSITION IN A MOLD, AFIRST SPIDER BLOCK MOUNTED ON SAID FIRST SHAFT AND HAVING A PLURALITY OFOUTWARDLY PROJECTING ARMS SLIDABLY RECEIVED IN OPENINGS FORMED IN THECORE SEGMENTS ADJACENT ONE OF THEIR ENDS, A SECOND SHAFT ROTATABLYCARRIED IN SAID FIRST SHAFT AND FIRST SPIDER BLCOK AND INTERPOSEDBETWEEN SAID CORE SEGMENTS, CAM MEANS ON SAID SECOND SHAFT ROTATABLETHEREWITH IN ONE DIRECTION TO ENGAGE SAID CAM FOLLOWERS AND FORCE SAIDCORE SEGMENTS UNIFORMLY OUTWARDLY FROM EACH OTHER TO EXPAND THECORE-FORMER, A SECOND SPIDER BLOCK ROTATABLY MOUNTED ON SAID SECONDSHAFT AT THE END OF SAID CAM MEANS REMOTE FROM SAID FIRST SPIDER BLOCKAND HAVING A PLURALITY OF OUTWARDLY PROJECTING ARMS PARALLEL WITH THEARMS ON SAID FIRST SPIDER BLOCK AND SLIDABLY RECEIVED IN OPENINGS FORMEDIN THE CORE SEGMENTS ADJACENT THEIR ENDS REMOTE FROM SAID FIRST SPIDERBLOCK, SPRING MEANS INTERCONNECTING EACH OF SAID CORE SEGMENTS TO SAIDSPIDER BLOCKS TO MOVE SAID CORE SEGMENTS INWARDLY UPON ROTATION OF THECAM MEANS IN AN OPPOSITE DIRECTION, SAID SPIDER BLOCK ARMS AND SPRINGMEANS LYING IN THE PLANES OF THE OBLIQUE CORE-FORMER AXES, AND MEANS ONSAID SPIDER BLOCKS AND CORE SEGMENTS BRIDGING AND CLOSING THE SPACESBETWEEN TOPS, BOTTOMS, AND SIDES OF SAID CORE SEGMENTS.